1. Field of the Invention
The invention relates to unitary button attaching apparatus and methods for attaching buttons to fabric.
2. Description of the Prior Art
A number of known devices have been developed to fasten buttons to a fabric or the like without use of thread and needle. However, many of the prior buttoning button fastening devices include several parts which are inconvenient to manipulate and are easily lost. Various unitary button fastening systems having pointed shafts or filaments extending from retaining members are known. In such unitary button fastening systems, the pointed members typically are passed through fabric to which the button is to be attached, through eyelets of a button, tracing U-shaped paths back through the fabric and through one or more apertures in the retaining elements from which the pointed filaments or members initially extend.
U.S. Pat. No. 3,785,009 discloses a button fastening system having a disc-shaped plate from which a pointed filament extends. The pointed filament is passed through the underside of the fabric and through one or more eyelets of a button disposed on the opposite side of the fabric. The pointed filament then is passed through a pair of elongated filament guide passages which are provided on the plate in respective intersecting planes. The pointed filament is pushed successively through the two guide passages to form a loop through which the free end portion of the filament is then pulled so that it is located in a groove of the plate extending under the loop. The filament is then tightened and the excess removed. However, the device described in U.S. Pat. No. 3,785,009 is difficult to use because of the need for considerable manipulation of the filament in order to tighten the filament and secure it to the base plate.
Another unitary button fastening element disclosed in U.S. Pat. No. 3,894,317 has similar shortcomings in that it is unwieldy to use, as it requires a number of manipulations to secure the elongated filament after it has been passed through eyelets of the button, back through fabric to a unitary base from which the filament originally extends.
The button fastener disclosed in U.S. Pat. No. 3,754,304 suffers from similar shortcomings as the previously mentioned devices; considerable dexterity is needed to grip the flexible filament of U.S. Pat. No. 3,754,304, pass it through a horizontal sleeve, grasp the end of the filament extending beyond the sleeve and tightly drawing it through the horizontal sleeve. Further, the button fastener of U.S. Pat. No. 3,754,304 is relatively expensive due to the cost of producing a roughened inner sleeve surface and a corresponding roughened filament surface to ensure adequate friction between the filament and the inner sleeve surface. This button fastener can not be manufactured with a roughened inner sleeve surface solely by low cost injection molding processes.
Accordingly, it is an object of the invention to provide a unitary button fastening device which requires less manipulation than prior button fasteners to reliably secure a button to fabric.
Another object of the invention is to provide a unitary button fastening device which is more reliable and yet less expensive to manufacture than prior button fasteners.
A simple unitary button fastening system is disclosed in U.S. Pat. No. 3,925,855 wherein a prong extending directly from the back of a button includes barbs which are pushed through fabric and retain the prong from being withdrawn through the fabric in the reverse direction. Excess prong material then is cut off. However, this device has the severe shortcoming that it is likely to damage the fabric, both during installation and as a result of damage done to the underside of the fabric by the prongs when a pulling force is exerted on the button.
Accordingly, it is still another object of the invention to provide a unitary button fastening system which does not damage fabric appreciably during installation of the button or afterward due to normal forces applied to the button.
U.S. Pat. No. 4,063,312 discloses a variety of other unitary button fastening systems, all of which are unduly costly to manufacure because of their complex structures and require an undue amount of manipulation and alignment of parts to fasten a button to fabric.
Accordingly, it is a primary object of the invention to provide a low cost, reliable unitary button fastening system which overcomes the shortcomings of the above described prior button fastening devices.